This invention relates generally to an antenna used in conjunction with a personal computer (PC) to communicate with a wireless network, and particularly to a retractable antenna that is compatible with a PC Card slot of a personal computer, such as a PCMCIA slot.
Portable communication devices, such as lap-top computers, palm-top computers, and PDA (personal digital assistants) are becoming common in offices. For these devices to communicate with a computer network, commonly referred to as a Local Area Network (LAN), the communication device must be able to attach to the network, typically through a LAN interface adapter attached to a LAN cable. Such LAN cable connections generally restrict the mobility of communication devices. Recently, networks have been developed that allow wireless communication. For the communication device to communicate with the wireless network, the communication device must have an antenna. Typically, the antenna is attached to a wireless network card inserted into the communications device. For example, in smaller devices such as laptops the card is inserted into a PC card slot, e.g., a PCMCIA (Personal Computer Memory Card Interface Association). To avoid signal interference with the mechanics of the communications device card slot, the antenna for the wireless communications device must be located outside of the device""s card slot or housing to function properly.
FIGS. 1 and 2 show a wireless network card assembly 10. The assembly 10 includes a wireless network card 12 and a removable antenna 14, where the removable antenna 14 connects to the wireless network card 12 with a cable 16 and connector 18. The wireless network card 12 is typically a PCMCIA adapter card that is sized to fit into a PCMCIA slot in a communications device. The PCMCIA standard size is approximately 55 mm in width, 85 mm in length, and 5 mm in depth. A first end 18 of the wireless network card 12 is designed to electrically connect to the communications device when the wireless network card 12 is inserted into the PCMCIA slot of the communications device. The second end 20 is designed to accept a connector 22 located on the end of cable 16. The antenna 14 may also have a base 24 to keep the antenna 14 in an upright position. When the antenna 14 is not in use, it may be detached. FIG. 2 shows the detachment of the connector 22 from the wireless network card 12. The antenna 14 is typically relatively large and bulky and if the user misplaces it, the communications device cannot generally communicate with the wireless network.
FIGS. 3 and 4 shows another wireless network card assembly 110. The wireless network card assembly 110 includes a wireless network card 112 and a removable antenna 114. This assembly 110 differs from the one shown in relation to FIG. 1 in that the antenna 114 is smaller and has an integral connector 122 that attaches to a second end 120 of the wireless network card 112. A first end 118 of the wireless network card 112 is designed to electrically connect to the communications device when the wireless network card 112 is inserted into a PCMCIA slot of the communications device. When the antenna 114 is not in use, it may be detached. FIG. 2 shows the detachment of the antenna 114 from the wireless network card 112. The antenna 114 is smaller than the antenna described in relation to FIG. 1, but again, if the user misplaces the antenna or breaks it, the communications device cannot communicate with the wireless network.
Antennas, such as the external detachable antenna (14, 114) described above, are generally required by the communications device for the wireless network to function properly. The antenna is one additional piece of equipment that could be forgotten or lost, requiring the customer to order and receive a replacement antenna before the wireless network can be accessed and used. In addition, this separate antenna, requiring assembly from the customer, increases the probability of functional problems, possibly requiring technical support.
FIG. 5 shows an extended PC card 210 that tries to solve the problems described above. The extended PC card 210 includes a wireless network card portion 212 with a fixed antenna portion 214. This PC card 210 differs from the wireless network card assemblies (10, 110), described above, in that the antenna 214 is integral with the PC card 210. This PC card helps solve the problem of misplacing or losing a removable antenna (14, 114). FIG. 6 shows the extended PC card 210 positioned in a PC card slot 230, as a PCMCIA slot, in a laptop computer 240. Unfortunately, any portion of a PC card 210 that extend outside the PC card slot 230 increases the likelihood of damage to the exposed portion during movement, in this case the fixed antenna portion 214. In addition, a PC card that extends outside the PC card slot will not allow a laptop computer to be stored in a typical laptop computer carrying case without first removing the extended PC card. This loose card then becomes much more likely to be misplaced or lost. Also, the extended PC card 210 shown, with its fixed external antenna portion 214, can interfere with other PC cards 235 positioned in adjacent PCMCIA slots in the computer 240 (see FIG. 7). The other PC cards 235 may require a connector attachment 240 or other types of access which would interfere 250 with the extended PC card 210.
In general, in one aspect, the invention features a PC card with a retractable antenna for use in interfacing between a communications device and a wireless network, the PC card having an interface card portion and an antenna portion, the interface card portion having a first end, and an opposite second end, the first end having an electrical interface compatible with the communications device, the second end having an opening for slidably receiving the antenna portion, the interface card portion being dimensioned to be inserted into the PC card slot of the communications device, the antenna portion being in electrical communication with the interface card portion and dimensioned to fit inside the interface card portion, the antenna portion being accessible through the opening in the interface card portion by a user, the antenna portion being configured to extend out of the cavity and retract into the cavity of the interface card portion such that when the antenna portion is retracted into the cavity the antenna portion is substantially contained inside the interface card portion.
Embodiments of the invention may include one or more of the following features. The PC card slot can be a PCMCIA slot. A locking mechanism can be located in the interface card portion, the locking mechanism being configured to selectably lock the antenna portion in the retracted position and release the antenna portion to be extended. A spring can be positioned in the cavity with one end attached to the interface card portion and the opposite end attached to the antenna portion, the spring being in a compressed state when the antenna portion is retracted in the cavity and the spring being in an extended state when the antenna portion is extended. The interface card portion can have internal rails and the antenna portion can have rail guides that are compatible with the rails such that during retraction or extension of the antenna portion the rail guides slide on the rails.
In general, in another aspect, the invention features a communications device for use in communicating with a wireless network, including a PC card slot, the PC card slot having an electrical connector; and a PC card sized to be insertable into the PC card slot, the PC card having a retractable antenna in electrical communication with the electrical connector, in an extended position a majority of the antenna being located outside of the PC card slot, in a retracted position a majority of the antenna being located inside the PC card slot.
Embodiments of the invention may include one or more of the following features. The PC card slot can be a PCMCIA slot. The PC card with retractable antenna can include an interface card portion, the interface card portion having a first end, and an opposite second end, the first having an electrical interface compatible with the communications device, the second end having an opening for slidably receiving the antenna portion, the interface card portion being dimensioned to be inserted into the PC card slot of the communications device; and the antenna portion can be in electrical communication with the interface card portion and dimensioned to fit inside the interface card portion, accessible through the opening of the interface card portion by a user, and configured to extend out of the cavity and retract into the cavity of the interface card portion such that when the antenna portion is retracted into the cavity the antenna portion is substantially contained inside the interface card portion. A locking mechanism can be located in the interface card portion, the locking mechanism being configured to selectively lock the antenna portion in the retracted position and release the antenna portion to be extended. A spring can be positioned in the cavity with one end attached to the interface card portion and the opposite end attached to the antenna portion, the spring being in a compressed state when the antenna portion is retracted in the cavity and the spring being in an extended state when the antenna portion is extended. The interface card portion can have rails on each side of the cavity and the antenna portion can have rail guides that are compatible with the rails such that during retraction or extension of the antenna portion the rail guides slide on the rails.
In general, in another aspect, the invention features a method of using a communications device in conjunction with a PC card having a retractable antenna for communicating with a wireless network, the method including providing a communications device having a PC card slot; inserting the PC card into the PC card slot, the PC card being in electrical contact with the communications device; extending the retractable antenna from the PC card, the retractable antenna extending out of the PC card slot; and communicating between the communications device and the wireless network.
Embodiments of the invention may include one or more of the following. The PC card slot can be a PCMCIA slot. The step of extending the retractable antenna can include unlocking the retractable antenna. The PC card can include an interface card portion and an antenna portion, the antenna portion being selectably extendible and retractable from a cavity in the interface card portion.
Embodiments of the invention may include one or more of the following advantages. A wireless network card with an integral antenna, compatible with a PC card slot of a portable communication device, can simply and compactly communicate with a wireless network. A wireless network card equipped with the retractable antenna of the present invention can avoid signal interface with the portable communication device, but does not have to be removed from the portable communication device during storage or transportation. The wireless network card can include a variety of electronic components, and its antenna can be quickly deployed by a user yet remain safely within the wireless network card when not in use.
Other features and advantages of the present invention should be apparent from the following description.